This invention relates to high voltage gas-insulated transmission lines, and more specifically relates to a novel termination structure for the flexible stranded conductor of a gas-insulated transmission line.
High voltage gas-insulted transmission lines are well known for carrying power in high voltage systems. Thus, in order to reduce the size of an electrical substation or an electrical transmission line, which deals with voltages, for example, in excess of about 100,00 volts, it is known to contain the high voltage components within grounded metallic housings which are filled with an insulation gas, such as sulfur hexafluoride under a few atmospheres of pressure.
The conductors for such systems commonly consist of a central conductor surrounded within a coextensive grounded housing which is filled with an electronegative gas such as sulfur hexafluoride or a mixture of electronegative gases. Such a system is shown in U.S. application Ser. No. 734,965, filed Oct. 22, 1976, in the name of P. C. Netzel and T. F. Brandt, entitled INSULATION SPACER FOR FLEXIBLE GAS-INSULATED TRANSMISSION LINE and assigned to the assignee of the present invention (C-1802[ATG/SD]). As shown in the above application, in order to make the transmission line flexible, it is common practice to use a corrugated grounded housing and a stranded central conductor, the strands of which are contained between inner and outer corrugated conductor tubes. The strands themselves are commonly wound in trapezoidal-shaped segments disposed around the central core tube and then covered with the outer corrugated tube sheath.
It is necessary to provide a connection to the central cable at the termination of the flexible gas-insulated bus. This connection is difficult to make because of the need to make firm connection to a multiplicity of strands. The terminal also must be easily made with conventional tools since connections are frequently made in the field, as where two bus sections are connected together or the bus termination is to be connected to some other piece of electrical apparatus in the field.